cellphone not repaired as agreed but did got paid

My daughter Chantel took her Samsung S6 to Mr. Haider Ali to be repaired. It had liquid damage. Mr. Ali said he will repair the S6 for R4000. This started 2 months ago. We got the phone back but still the phone had a problem. We explained to Mr. Ali employees the problem. Two weeks after we got phone back. But still not fixed. We took it back for 3rd time. We waited 3 weeks and got phone back they told us we must pay additional r1500. But the phone is still not fixed. Now is this the service Mr. Ali is offering the people ofSouth Africa. It is a discrace